O'Sullivan then told Carter it was his turn to play, sparking Carter to respond: "Thank you very much, very nice of you."

"Stop being angry then," O'Sullivan said.

Ronnie O'Sullivan barges past Ali Carter (Image: Eurosport)

Ronnie O'Sullivan barges past Ali Carter (Image: Eurosport)

Ali Carter smirks (Image: Eurosport)

Referee Paul Collier intervened and said: "Right fellas just play on", with O'Sullivan then saying he was "cool as a cucumber".

O'Sullivan trailed 11-9 at the mid-session interval, with Carter needing two more frames for victory.

Dennis Taylor, the 1985 world champion, said on the BBC: "I've never seen that at the Crucible in 41 years."

Ronnie O'Sullivan gestures (Image: Eurosport)

Ronnie O'Sullivan gestures (Image: Eurosport)

Carter grumbled before the match began that snooker had become 'The Ronnie O'Sullivan Show. He also failed to shake hands with referee Paul Collier after the second session on Friday, a possible sign of irritation at his lead being whittled down.

He led 9-7 overnight and although O'Sullivan won the first frame of Saturday's afternoon session, Carter did not let him encroach any closer before the interval.

Ronnie O'Sullivan shakes hands with Ali Carter (Image: BBC)

Carter came into the match having never beaten his former practice partner in a major match. Their four previous Crucible clashes had all gone to O'Sullivan, including their duels in the 2008 and 2012 finals.

But this time it was Carter closing in on the win, and he took the first frame after the resumption to move 12-9 in front.

Carter jumped on an early chance in the next frame and soon clinched a 13-9 victory, setting up a quarter-final date with Mark Williams or Robert Milkins.

Carter pumped his fist in delight as he left the arena.

On the incident, he said: "I just thought, ‘Listen, I’m not intimidated by Ronnie like a lot of other players are, I’ve been through harder things than that in my life’.